Tool use and consumption of beef began 3.2 million years ago, according to a study published in the journal “Nature.”

Researchers found evidence that hominids--the more primitive ancestors of modern humans--used stone tools to cut meat for over 3.2 million years.

The finding suggests that the use of tools and meat consumption by hominids happened 800,000 years earlier than previously thought.

Bones found in Ethiopia display stone cuts and indications that the marrow was removed forcibly.

The research, published in the journal “Nature,” challenges many theories about the behavior of the ancestors of men.

The oldest tool known to archaeologists before this discovery has been found in the region of Gona, in Ethiopia.

Until then, scientists believed that the first human ancestors who used tools were of the genus Homo, the genus of the same species as contemporary humans, Homo sapiens. This would have been about 2.5 million years ago.

The new discovery in the Ethiopian region of Dikika, indicates that the tools had been used between 3.2 million and 3.4 million years ago. The date of the tools was determined by analyzing volcanic rocks in that area.

A battery of tests showed that cuts and scratches were made on the bones before they fossilized. An analysis showed that there were even pieces of rock in the bones.

The only species of hominids in the region of Dikika known to scientists is Australopithecus afarensis, which became famous after the discovery of the fossil called “Lucy.” She came from a species of hominid that was an ancestor of Homo, according to one hypothesis.

One of the authors of the study published in “Nature,” Zeresenay Alemseged, a paleoanthropologist at the California Academy of Sciences, said the discovery represents an important turning point in what is known about the genus A. afarensis.

“For thirty years, nobody could put the stone tools in their hands, and we did it first,” said Alemseged.

“We’re showing for the first time that bone tools are not unique to Homo or species related to Homo. We have an A. afarensis behaving like a Homo both in the use of tools and in meat consumption. This is another feature of Homo that can act as a link between A. afarensis and the genus Homo.”

However, the study’s findings are based on a small number of bones. There is no evidence that A. afarensis made the tool by using larger pieces of rock or simply used some sharp rocks they found.

Alemseged and Shannon McPherron, an archaeologist at the Max Planck Institute in Leipzig, Germany, say the scientists’ next task is to return to the site and continue searching for clues. “It’s always difficult to assign a behavior to a hominid in particular,” said McPherron. “We are never lucky enough to find a dead hominid with a tool in his hand.”

The scientist Chris Stringer of the Natural History Museum, London, cautions that care should be taken before drawing more definitive conclusions. “We must be cautious,” he said, “because we have only a few bones with some marks on them. We would like to be able to associate them with the tools to really have a case.”

He recognizes that if the research is evidence based, the study brings something very new to science.